Affected: Linux

In the Linux kernel, the following vulnerability has been resolved:

afs: Fix reinitialisation of the inode, in particular ->lock_work

It seems that initalising afs_vnode::lock_work a single time in the slab's init function isn't sufficient for work_structs. This results in the DEBUG_OBJECTS debugging stuff producing a warning occasionally when running the generic/131 xfstest:

ODEBUG: activate not available (active state 0) object: 0000000016d8760f object type: work_struct hint: afs_lock_work+0x0/0x220 WARNING: lib/debugobjects.c:629 at debug_print_object+0x4b/0x90, CPU#3: locktest/7695 ... CPU: 3 UID: 0 PID: 7695 Comm: locktest Tainted: G S 7.1.0-build3+ #2771 PREEMPT ... RIP: 0010:debug_print_object+0x65/0x90 ... Call Trace: <TASK> ? __pfx_afs_lock_work+0x10/0x10 debug_object_activate+0x122/0x170 insert_work+0x25/0x60 __queue_work+0x2e0/0x340 queue_delayed_work_on+0x48/0x70 afs_fl_release_private+0x57/0x70 locks_release_private+0x5c/0xa0 locks_free_lock+0xe/0x20 posix_lock_inode+0x55f/0x5b0 locks_lock_inode_wait+0x81/0x140 ? file_write_and_wait_range+0x50/0x70 afs_lock+0xcd/0x110 fcntl_setlk+0x10d/0x260 do_fcntl+0x24e/0x5b0 __do_sys_fcntl+0x6a/0x90 do_syscall_64+0x11e/0x310 entry_SYSCALL_64_after_hwframe+0x71/0x79

Fix this by reinitialising ->lock_work after allocating an inode.

Also, flush ->lock_work when the inode is being evicted to make sure it's not still running.